Although my iPhone screen has enough grease on it, we are now seeing some that is useful. GreasePocket is a Greasemonkey/Kit-like plugin that allows you to write userscripts for your iPhone.

Not only can you access the DOM and such, but you can access device APIs themselves. Thus, you could write a GreasePocket script that talks to your contacts list, or your camera. There are obvious security concerns here, and the team hasn’t fixed the issues that Greasemonkey itself had to deal with.

To help with this issue, Ishan Anand and Ajay Kapur are looking to opensource the project to get some help.